where \(\big (\Omega ^1(B),\mathrm {d}\big )\)  is the differential calculus on \(B\)  that is
determined by the \(B\) -subbimodule \(N_B := (\ker \mu _B)\cap N\subseteq \Gamma ^1(B)\) .
Equivalently, this differential calculus may by
obtained from \(\big (\Omega ^1(A),\mathrm {d}\big )\)  as a restriction, i.e.,
\(\Omega ^1(B) = B \mathrm {d}(B)\subseteq \Omega ^1(A)\) , see, e.g.,
[1]}.
The short exact sequence (REF ) will be referred to as the Atiyah sequence
for the concordant differential calculi \(\big (\Omega ^1(A),\mathrm {d}\big )\)  and
\(\big (\Omega ^1(H),\mathrm {d}\big )\) .
